1. Field of the Invention
The present invention generally relates to a method and a device for adaptive color correction and, more particularly, to a method and a device for adaptive color correction by weighting procedure according to the pixel luminance so as to adjust the pixel chrominance saturation.
2. Description of the Prior Art
With the arrival of the digital era, digital information products are replacing analog products. One example is that the digital TV gradually replaces the traditional analog TV. Meanwhile, the video information is recorded and distributed by digital media instead of traditional tapes. Consequently, the quality of digital images has become a major issue in the industry.
The digital image is recorded in pixels. The colors of each pixel associates with its brightness and chromaticity, are seen as various combinations of the so-called primary colors, red (R), green (G), and blue (B). Moreover, the quality of digital images primarily depends on the brightness, contrast, and chromaticity of the whole picture.
As for digital image processing, the prior art converts RGB signals into luminance (Y) and chroma (U and V) signals, and then adjusts these signals to correct the brightness, contrast, and chromaticity of digital images. Generally, a problem will occur while directly adjusting the luminance and chrominance signals of each pixel in a digital image.
Conventionally, the luminance (Y) and chrominance (U and V, or Cb and Cr) signals are handled individually. Therefore, the color saturation is adjusted independently of the luminance of each image pixel. Sometimes, color noise occurs in the dark pictures if video/image processing of a television is not properly performed.
Accordingly, there is need in providing a method and a device for adaptive color correction so as to effectively correct color on the digital image under low luminance.